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Stuck mashes

Brewing is a combination of processes, sometimes very intricate processes. The brewer must draw upon their knowledge, experience, and creativity. Utilizing a brew house full of equipment, they must somehow convert raw ingredients, like malted barley, into a fizzy alcoholic, sweet and bitter beverage we know as beer.

“Mashing is the brewer’s term for the hot water steeping process which hydrates the barley, activates the malt enzymes, and converts the grain starches into fermentable sugars.” – (How to Brew, Palmer)

The mashing process varies from brewer to brewer, but the basic principles are the same. The big macro breweries have giant, shallow mash tuns. This prevents the heavy weight of grain and liquid from compacting the grain bed. A compact grain bed will inhibit a good lauter, the separation of liquid from grains.

The strain of a small setup, combined with limited equipment, is a curse that many small breweries and home-breweries deal with on a daily basis. Limited capital means a smaller mash tun, probably one that is higher than it is deep.

Our mashes at the Papa Louie’s Brewhaus were getting worse and worse. Eight hour brew days morphed into nineteen hour nightmares, barley extracting enough sweet liquor from the mash to fill up a barrel half full. It seemed that fluid dynamics were being violated: how can this hot liquid be stratified at the top? I was stumped, especially since we had been stirring the crap out of these mashes during the strike.

Even my wife and brewbaby were stumped.

Turns out, I was doing it all wrong. Let me share with you some of the tricks I learned to get a (near) perfect mash.

Lay a bed of rice hulls on top of your false bottom / manifold. This will prevent little bits of flour from the grist impregnating themselves upon the tiny perforations.

Keep a layer of water over the grain bed. This will help prevent a compacted grain bed.

Raise your temperature throughout the mash. We do this with a simple process: Drain sweet liquor into a wort grant, pump this liquid through a HERMS coil within our Hot Liquor Tank, return to the top of the mash without splashing or losing too much heat.

Try to reach a mash-out temperature, in the range of 168*F before sparging. This will deactivate enzymes that will extract tanic flavors from the grain. What is a tanic flavor, you ask? If you suck on old tea bag, you will find out.